Prototype is rendered for each point instance

[xsisupport]

Describe the bug
For each instance created by an Instancer LOP, the prototype also shows up in the render.
The attached scene has this setup:

• point instancer with changing point count per frame
• velocity blur (because of changing point count)
• pscale set on points with a marked scale difference from prototypes
• multiple time samples exists (whether with a cache node or when written to usd file)

If you write out a usd file and then load it as a sublayer, it has the same problem.
Note that Karma didn't render the sublayer properly either.

The viewport renders were a bit erratic. As I played around with the scene, the motion blur would disappear sometimes. Then come back. Then the problem would go away and I had to re-load the scene to repro again.

Repro data set

support_case_00031665.zip

Screenshots
If you increase the shutter size, you can clearly see it's the prototype torus that renders:

Sometimes, not always, if you add an Arnold Render Settings LOP and enable Ignore Motion Blur, you also see the prototype torii:

In a new Houdini scene, with the usda loaded as a Sublayer, this is what Karma rendered (in the original scene, the Karma render was ok):

Used Software Versions

• Arnold: Latest
• Houdini

[autodesk-oss-arnold-bot]

Issue synced internally to ARNOLD-15915